Development degree,basic patterns and influencing factors of urban polycentric spatial structure in China:Based on empirical study on 297 prefecture-level or above cities
To compensate for the limitations of case fragmentation,inconsistent standards,misused methods of identifying city centers,and incomparable conclusions in the established Chinese polycentric spatial structure studies,this study aimed to identify all the city(sub)centers of 297 Chinese prefecture-level or above cities in 2019 by using fine-grained Landscan ambient population data and integrating spatial autocorrelation analysis with polycentric regression models.We also measured the degree of urban polycentricity using three indicators:the number of city centers,the relative distance between city centers,and the balance of center development.Then,we summarized ten types of urban spatial structure patterns based on the combination of the three poly-centricity indicators mentioned above.The study identified a total of 863 centers in 297 prefecture-level or above cities in 2019,and learned the theoretical density and density gradient of each center in every city through the negative exponential function.These findings served as a comprehensive examination of the under-lying base map of the polycentric structure of Chinese cities and formed the basis for subsequent longitudinal tracking analyses.Our study revealed that in 2019,monocentric,bicentric and polycentric cities accounted for approximately 29％,20％and 45％of the total,while 5.7％of the cities remained in a dispersed pattern.We found that,except for a few cities with a dispersed pattern,the more centers,the fewer the corresponding cities.Developed,mountainous,provincial border cities,and small and medium-sized cities with an evenly distrib-uted urban population were more likely to form sub-centers far from the main center.Larger cities with a cluster layout and smaller cities with strong counties but weak districts were more likely to develop multiple(or dual)centers with equal density and balanced influence,while the main center of circle-sprawling cities tended to dominate the population distribution in the whole region,and their spatial patterns showed a polarized trend.Our study demonstrated that the level of social and economic development was the primary factor in shaping the polycentric spatial structure of Chinese cities,and the fluctuation and variability of natural topography also objectively contributed to the growth of urban polycentricity.However,out-migration public policies such as government relocation and the construction of industrial development zones and new town did not have a signi-ficant effect on urban polycentricity.It was also difficult for road construction to effectively promote the growth of new sub-centers.Therefore,the polycentric spatial structure was the product of high-level socio-eco-nomic development rather than an artificial creation through leapfrogging planning.
NETL
NSTL
万方数据
